This pebble/cobble derives from the fluvial Pleistocene Meuse river terrace. It was generated as a result of the erosion of Paleozoic rocks of the Ardennes, Vosges area and the Rhenisch Massif (Dreesen et al. 2014). "Vallei van de Kikbeekbron" is a former gravel and sand quarry, now nature reserve situated in the High campine (Limburg) area.
Dreesen R., Janssen J. & Van Uytven D. 2014. Het grind ontleed: samenstelling en herkomst van de stenen in het Maasgrind. LIKONA Jaarboek, 24, Provinciaal natuurcentrum Limburg: 18-35.